Lunch was not served. Seven hundred students reportedly went home hungry after their school day.

India's free school lunch program is the largest in the world. The program was started in the mid-1990s with two goals: to fight chronic hunger and child malnutrition and to increase school enrollment and attendance.

As many studies have shown, the program has reached these goals. The "Mid-Day Meal Program" currently feeds about 120 million of India's poorest children. "Food is cooked in 12 lakh [1.2 million] schools," says Dipa Sinha, an economist at the Center for Equity Studies in New Delhi.

It is also a program that has made headlines for its missteps, one of which was tragic.

In 2013, 23 students at a school in the Chapra district of Bihar died after eating food contaminated with pesticides. Many more fell ill. A government investigation later found that, like most schools in the state, this school had no separate kitchen or storage place for the food items. As a result, ingredients were stored in the principal's house, right next to pesticides stored for her farm.

Since then, there's been no tragedy of similar scope. But there are worms. And lizards.

Earlier this summer, a child found a dead lizard in the lunch served at his primary school in the city of Bhagalpur, on the Ganges River in the state of Bihar. Later that day, 16 students complained they were feeling dizzy and had to be admitted to the local primary health care center. A government investigation later found that the animal had fallen into the meal while it was being cooked.

In these cases — and other instances where students became sick after eating a contaminated school lunch — the cause is often a lack of proper storage facilities.

The rice and wheat supplied to schools come from government warehouses, says Sinha, who was a member of a team appointed by the Indian government to track the school lunch program in different states. This past year, the government bought more grains from farmers than it had room to store them, she says. "A lot has been stored in the open."

Schools are also short on storage space. The government sends grains to schools every two or three months. And many schools around the country don't have a separate kitchen or larder to store the grains.

This is monsoon season, says Sinha. Insects thrive in the damp weather. "So if there's no storage in the schools, then it's a problem."

Back in Bihar, where most of these recent incidents have occurred, local activists agree. "You have to improve the facilities [in schools]," says Rupesh Kumar, a longtime food rights activist.

Since the 2013 poisoning in Bihar, the government has been building separate kitchens in schools. "As of March of this year, 2,000 schools had kitchen sheds," says Kumar. But thousands more are yet to be built.

There's also a need to better train cooks about best practices in the kitchen, says Kumar. Cooks at schools are often illiterate or poorly educated and aren't aware of health standards. He says the government has already given schools in Bihar a set of "standard operating procedures," or guidelines to maintain health and sanitation standards. But there's no way to ensure that the cooks follow those guidelines.

Ultimately, he says all of this reflects a lack of monitoring and accountability.

Currently, a teacher is assigned to monitor the program and make sure everything runs smoothly, says Kumar. Teachers do this on top of regular duties and are not paid extra. "One person is overseeing everything," he says. "This is the main problem."

The problems can be fixed, says Sinha. For example, the states of Tamil Nadu and Gujarat have created a separate position for a "noon meal organizer." As a result, she says, their school lunch programs have fewer problems than do other areas.

The Indian government has appointed a handful of independent committees to periodically monitor programs in randomly selected schools. But such efforts need to be more comprehensive, says Sinha.

Meanwhile, despite all these cases of contaminated food, kids haven't stopped eating the free lunches — a sign of how much they depend on the Mid-Day Meal Program.